I FINALLY FOUND OUT WHY THIS HAPPENS. You see this all the time when there’s a fight or a scrum and suddenly everyone pairs up with a member of the opposite team and they just sort of …hold each other.

Someone on reddit asked about it. And it turns out there’s a logical-ish reason:

all of the other players pair off with their man to prevent anyone else entering into the fight … so it’s a form of self policing.

[…] The players basically want to prevent 2 on 1, etc. fights and by finding a “hugging” partner so there’s no ganging up on one guy, even on accident. They do it because it’s fair. And it’s kind of cute sometimes.